Over Restlessness, lask of sleep ... in kids

Patient

Q:Hello,
my name is Ani & I'm 18 years old & i reside in india & I'm just a student!
my uncle is married and has a son and a daughter !
I really don't want to twist any information. So, let me go to the issue right away
his son is almost 10 yrs old. Initially i noticed very-aggressive behavior displayed by him and i didn't care and I was like "Oh! Child, ha ha".
But, today he displays v.v. aggressive behavior which isn't tolerable!
I've heard lot of incidents created by him recently. here are a few
INCIDENT 1 :
recently they had a function in their home and a few guests gifted them a bouquets, due to some reason he took the bouquets and tore them apart as if he was extremely angry about something.

INCIDENT 2:
Recently My uncle and my Aunt had a car accident in Daylight in a empty road. After a lot of investigating with the car, it was found out that the car played no role in the accident!The cause of the accident is UNKNOWN! I tried to co-relate to this incident with the next.

INCIDENT 3:
While my Dad was driving the car and the boy as surprising guest in it, suddenly the boy for no reason pulled the hand-break! It was close since the car was travelling in very low speed.

I want to know if the behavior exhibited by the boy is natural or due to some medical reason.?

Additional information:
As far as i know, their family has NO problems. My uncle works from home, Aunt is a house wife, They have no financial problems, they live in a big house and both of them are well educated.

Symptoms: Over Mischievous
over playful
He doesn't care about "After" Effects of anything! even after he puts his hand in the fire !
Doesn't sleep properly
Over Restlessness !

Plz my parents are keeping this thing as a secret, and i just a curious student who just want to know more about this !

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